Law enforcement and crime fighting often involve armed conflict within close quarters of a house, apartment complex, warehouse or other building where the line of sight is often less than tens of feet and the potential for multiple opponents to attack from a concealed position may be high.
Police also may confront felons in a tenement house where a standard sidearm is available to confront hostilities that may arise. Similarly, a soldier may be tasked with operations in a city involving a mix of non-combatants and potential hostiles in a building.
More and more, military forces are required to engage an enemy in an urban environment where a handgun would be of greater operational support than a rifle. Confined spaces for close combat do not lend themselves to wielding a rifle for fast reactions to confront possible multiple armed hostiles.
Present technology discloses means for attaching accessories to a handgun in a fixed position and orientation, such as facing forward along the barrel line of sight. Laser sights and scopes are the most common attachment.